The development of information infrastructures that make ecological research data available has increased in recent years, contributing to fundamental changes in ecological research. Science and Technology Studies (STS) and the subfield of Infrastructure Studies, which aims at informing infrastructures’ design, use, and maintenance from a social science point of view, provide conceptual tools for understanding data infrastructures in ecology. This perspective moves away from the language of engineering, with its discourse on physical structures and systems, to use a lexicon more “social” than “technical” to understand data infrastructures in their informational, sociological, and historical dimensions. It takes a holistic approach that addresses not only the needs of ecological research but also the diversity and dynamics of data, data work, and data management. STS research, having focused for some time on studying scientific practices, digital devices, and information systems, is expanding to investigate new kinds of data infrastructures and their interdependencies across the data landscape. In ecology, data sharing and data infrastructures create new responsibilities that require scientists to engage in opportunities to plan, experiment, learn, and reshape data arrangements. STS and Infrastructure Studies scholars are suggesting that ecologists as well as data specialists and social scientists would benefit from active partnerships to ensure the growth of data infrastructures that effectively support scientific investigative processes in the digital era.
Article
Data Infrastructures in Ecology: An Infrastructure Studies Perspective
Florence Millerand and Karen S. Baker
Article
Surface Irrigation
Luis S. Pereira and José M. Gonçalves
Surface irrigation is the oldest and most widely used irrigation method, more than 83% of the world’s irrigated area. It comprises traditional systems, developed over millennia, and modern systems with mechanized and often automated water application and adopting precise land-leveling. It adapts well to non-sloping conditions, low to medium soil infiltration characteristics, most crops, and crop mechanization as well as environmental conditions. Modern methods provide for water and energy saving, control of environmental impacts, labor saving, and cropping economic success, thus for competing with pressurized irrigation methods. Surface irrigation refers to a variety of gravity application of the irrigation water, which infiltrates into the soil while flowing over the field surface. The ways and timings of how water flows over the field and infiltrates the soil determine the irrigation phases—advance, maintenance or ponding, depletion, and recession—which vary with the irrigation method, namely paddy basin, leveled basin, border and furrow irrigation, generally used for field crops, and wild flooding and water spreading from contour ditches, used for pasture lands. System performance is commonly assessed using the distribution uniformity indicator, while management performance is assessed with the application efficiency or the beneficial water use fraction. The factors influencing system performance are multiple and interacting—inflow rate, field length and shape, soil hydraulics roughness, field slope, soil infiltration rate, and cutoff time—while management performance, in addition to these factors, depends upon the soil water deficit at time of irrigation, thus on the way farmers are able to manage irrigation. The process of surface irrigation is complex to describe because it combines surface flow with infiltration into the soil profile. Numerous mathematical computer models have therefore been developed for its simulation, aimed at both design adopting a target performance and field evaluation of actual performance. The use of models in design allows taking into consideration the factors referred to before and, when adopting any type of decision support system or multicriteria analysis, also taking into consideration economic and environmental constraints and issues.
There are various aspects favoring and limiting the adoption of surface irrigation. Favorable aspects include the simplicity of its adoption at farm in flat lands with low infiltration rates, namely when water conveyance and distribution are performed with canal and/or low-pressure pipe systems, low capital investment, and low energy consumption. Most significant limitations include high soil infiltration and high variability of infiltration throughout the field, land leveling requirements, need for control of a constant inflow rate, difficulties in matching irrigation time duration with soil water deficit at time of irrigation, and difficult access to equipment for mechanized and automated water application and distribution. The modernization of surface irrigation systems and design models, as well as models and tools usable to support surface irrigation management, have significantly impacted water use and productivity, and thus competitiveness of surface irrigation.
